According to DEA officials, criminals first sell illegal prescription drugs online through websites they operate, and then once a customer has put in their personal information and made a purchase, the criminals use the information to black mail and extort them.

The websites seem so simple, so inviting -- buy prescription diet pills or sleep-aids without a prescription. But it could be a trap.

A few clicks on certain websites can lead to phone calls that sound like this: "This is officer James Kashin. If you and your wife don't call me back you are going to jail."

Or this: "This is special agent David Brown. We are going to bring you in, in custody, with criminal charges for medication from overseas."

It's all part of an elaborate scam, including the alleged law enforcement phone calls.

According to DEA officials, criminal scam artists first sell prescription drugs online through websites they sometimes operate. After customers input their personal information and make a purchase, the criminals can use the information to blackmail and extort them.

Scammers pose as federal drug enforcement agents, even use actual agents' names, when they make threatening phone calls to thoroughly scare their marks, but then the fake agents offer their victims a lifeline. The caller tells his victims that they have a choice -- either they pay up by a certain deadline and their names will be cleared, or they will be charged as suspects in a criminal investigation and face jail time.

"Basically he wanted me to pay $1,500," said Kesha Howell, a victim of the scam.

"He's got you in such a panic state that by the time he offers you the money, I mean really, that's a no-brainer. Just tell me how much and if I can afford to do it, I'm in," said Darren Dutil, another victim.

Victims of this scam say the phone calls sound authentic and are genuinely terrifying because the person on the other end has all of their personal information.

"He was very calm, cool, but very intimidating. He knew things about me. He had legit information on me and that's what was so scary," Howell said.

"I was ready to call my wife and kids and say, 'hey look, see you all later. I'm obviously going to be gone for a while,'" Dutil said.

Another victim, who didn't want his name revealed, said he got a call from the scammers and fake DEA agents actually showed up at his house in suburban Fort Worth, Texas.

"They pulled up in a black SUV, right there at the driveway. Two white males got outside, stood beside the truck, and a slender 5-10, 5-11 black male came toward me with black wavy hair," he said.

In the end, he said he didn't fall for the scam, but he admitted he came close.

But Carolyn Sirek, a legal secretary from Joshua, Texas, fell into the trap and accepted the buyout option after receiving the scamming calls. According to her husband Dan Sirek, Carolyn went into a local Wal-Mart and wired the scammers the money through Western Union.

Very often, after one payment, the scammers come back for more. Carolyn Sirek was apparently so upset and scared about what happened that she shot and killed herself in her backyard. Her husband said he found her with a bullet hole in her chest.

Thousands of victims, many of whom have paid the scammers, have called the DEA hotline for help. Officials believe several of these people have shelled out thousands of dollars in the extortion and that the operation is being run out of the Dominican Republic.

The DEA has indicted 11 Dominican men, but as of yet, those men have not been arrested. Agents told ABC News they are working with the Dominican government to have the suspects extradited to the United States, and are investigating other groups operating similar scams.